Arterial elasticity in obese subjects with coronary slow flow phenomenon.

BACKGROUND: Coronary slow flow phenomenon (CSFP) is a functional and structural disease that is diagnosed by coronary angiogram. OBJECTIVES: To evaluate the possible association between CSFP and small artery elasticity in an effort to understand the pathogenesis of CSFP. METHODS: The study population comprised 12 patients with normal coronary arteries and CSFP and 12 with normal coronary arteries without CSFP. We measured conjugated diene formation at 234 nm during low density lipoprotein (LDL) oxidation, as well as platelet aggregation. We estimated, noninvasively, arterial elasticity parameters. Mann-Whitney nonparametric test was used to compare differences between the groups. Data are presented as mean +/- standard deviation. RESULTS: Waist circumference was 99.2 +/- 8.8 cm and 114.9 +/- 10.5 cm in the normal flow and CSFP groups, respectively (P = 0.003). Four patients in the CSFP group and one in the normal flow group had type 2 diabetes. Area under the curve in the oral glucose tolerance test was 22% higher in the CSFP than in the normal group (P = 0.04). There was no difference in systolic and diastolic blood pressure, plasma concentrations of total cholesterol, triglycerides, high density lipoprotein, LDL and platelet aggregation parameters between the groups. Lag time required until initiation of LDL oxidation in the presence of CuSO4 was 17% longer (P = 0.02) and homocysteine fasting plasma concentration was 81% lower (P = 0.05) in the normal flow group. Large artery elasticity was the same in both groups. Small artery elasticity was 5 +/- 1.5 ml/mmHg x 100 in normal flow subjects and 6.1 +/- 1.9 ml/mmHg x 100 in the CSFP patients (P = 0.02). CONCLUSIONS: Patients with CSFP had more metabolic derangements. Arterial stiffness was not increased in CSFP.

Ezetimibe's effect on platelet aggregation and LDL tendency to peroxidation in hypercholesterolaemia as monotherapy or in addition to simvastatin.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: Statins demonstrate a pleiotropic effect which contributes beyond the hypocholesterolaemic effect to prevent atherosclerosis. WHAT THIS STUDY ADDS: Ezetimibe has an antioxidative effect when given as monotherapy or as an add-on to the statin, simvastatin. AIMS To investigate the effect of lowering low-density lipoprotein-cholesterol (LDL-C) on platelet aggregation and LDL tendency to peroxidation by ezetimibe alone or with simvastatin in hypercholesterolaemia. METHODS: Sixteen patients with LDL-C >3.4 mmol l(-1) received ezetimibe for 3 months (Part I). Twenty-two patients on fixed simvastatin dose with LDL-C >2.6 mmol l(-1) were enrolled (Part II). Part II patients continued simvastatin treatment 20 mg day(-1) for 6 weeks, then received 20 mg day(-1) simvastatin combined with ezetimibe 10 mg day(-1) for another 6 weeks. The tendency of LDL to peroxidation measured by lag time in minutes required for initiation of LDL oxidation and by LDL oxidation at maximal point (plateau) was measured before and after ezetimibe treatment. RESULTS: Part I: Ezetimibe 10 mg daily for 3 months decreased plasma LDL-C level 16% (P = 0.002), prolonged lag time to LDL oxidation from 144 +/- 18 min to 195 +/- 16 min (P < 0.001), decreasing maximal aggregation from 83 +/- 15% to 60 +/- 36% (P = 0.04). Part II: Serum level LDL-C decreased 23% (P = 0.02) and lag time in minutes to LDL oxidation was prolonged from 55.9 +/- 16.5 to 82.7 +/- 11.6 (P < 0.0001) using combined simvastatin-ezetimibe therapy. There were no differences in platelet aggregation. CONCLUSIONS: Ezetimibe was associated with decreased platelet aggregation and LDL tendency to peroxidation. Treatment with ezetimibe in addition to simvastatin has an additive antioxidative effect on LDL.